Investigation on ultrasonic-assisted grinding of characteristics of C/SiC composites by brazed and electroplated diamond wheels

Ultrasonic-assisted grinding (UAG) can effectively reduce the grinding force and improve the machining quality of carbon fiber-reinforced ceramic matrix composites (C/SiC) due to its excellent machining performance. Many researches have shown that the machining performance of UAG is closely related to the kinematic trajectory characteristics of the abrasive grains, so the surface morphology of diamond grinding wheels with various process preparations has an important influence on the grinding quality. In this paper, to investigate the performance of UAG of C/SiC composites with diamond grinding wheels prepared by different processes, UAG experiments were carried out on C/SiC composites using diamond grinding wheels prepared by brazing and electroplating processes. The trajectories of the abrasive grains and the maximum undeformed chip thicknesses with different abrasive grain protrusion heights were analyzed and the impact of the two diamond grinding wheels and the grain mesh size on the grinding force, surface roughness, and surface morphology were comparatively investigated. The results indicated that the grinding force and surface roughness obtained by brazed grinding wheels were reduced by 13 ~ 36.05% and 5.95 ~ 19.3% compared with electroplated diamond wheels at 240#, respectively. The brazed grinding wheels could improve the grinding surface morphology to a certain extent. However, the surface roughness value fluctuated with the increase of abrasive grain size. Additionally, the protrusion height of the abrasive grain of the brazed diamond wheels is more favorable for the UAG effect and the grinding wheels are less prone to clogging.